The present invention relates to an alarm system for a desktop clock capable of generating an audio alarm in the form of, for example, a voice message or the sound of running water at a preset wake-up or retiring time. More particularly, the invention relates to an alarm system for a desktop clock provided with an improved wake-up time indicating alarm unit on the main body, in which an hour hand alarm connecting gear wheel and a minute hand alarm connecting gear wheel are separately provided to facilitate the user""s manipulation of the time setter on the casing in setting the wake-up and retiring time indication hands to a desired call time, thereby generating an audio alarm that reminds the user in a timely manner of the retiring time and a snooze time period of less than one hour, as well as the wake-up time.
In the mechanism of the conventional alarm system for desktop clocks, as the user rotates and manipulates an alarm time setter, a gear wheel fixedly associated with the alarm time setter is actuated to rotate both a gear wheel connected to a wake-up time indication hand and an hour hand gear wheel in the one direction. The hour hand gear wheel in turn rotates a minute hand gear wheel to set a predetermined call time. When the preset call time is reached, the stopper of the alarm gear wheel gets out of the groove of the hour hand gear wheel to raise both the hour hand gear wheel and the minute hand gear wheel. As a result of this, the contact of the minute hand gear wheel connects with that of a power terminal connected electronically to an alarm buzzer to generate an alarm sound. The alarm system is provided with an alarm switch on the move of the timepiece, particularly, an alarm on/off selection switch or a push-bottom which is provided on the front side, backside or topside of the casing of the desktop clock. Such conventional alarm systems mostly have a single function to generate, sometimes in an untimely manner, an alarm sound at a predetermined wake-up call time as preset by the user and disturb the surrounding people with an annoying alarm sound for a long time.
Furthermore, the convention alarm systems sometimes miss the preset call time so that those users not in the habit of sleeping a sound sleep at a predetermined time such as students preparing an examination, children and workers may have a lack of sleeping hours and suffer from fatigue and bad health.
It is the objective of the present invention to solve the problems of the previous type and to provide a novel alarm system for a desktop clock which is provided with a retiring time indicating alarm unit and a snooze time indicating alarm unit to set a snooze period of less than one hour with modified audio alarm generating and electrical connecting structures, in contrast to the arrangement of the conventional desktop clock which only has a time indicating and alarm ringing function using the operation of an oscillator connected to a circuit board with the power on.
To achieve the objective of the present invention, there is provided an alarm system for a desktop clock including: a retiring time rotatable gear wheel inserted into the casing of the desktop clock; a wake-up time rotatable gear wheel inserted in the casing of the desktop to be coaxially rotated with the retiring time gear wheel; a retiring time indication hand fixedly inserted in the axial top end of the retiring time gear wheel; a first intermediate gear wheel; an hour hand alarm connecting gear wheel having the same number of toothed gears as the retiring time gear wheel, wherein the first intermediate gear wheel and the hour hand alarm connecting gear wheel are sequentially geared with the retiring time gear wheel; an hour hand gear wheel; a second intermediate gear wheel; an hour hand alarm ringing gear wheel having twice as many toothed gears as the hour hand gear wheel, wherein the second intermediate gear wheel and the hour hand alarm ringing gear wheel are sequentially geared with the hour hand gear wheel; a third intermediate gear wheel; a minute hand alarm connecting gear wheel having the same number of toothed gears as the wake-up time gear wheel, wherein the third intermediate gear wheel and the minute hand alarm connecting gear wheel are sequentially geared with the wake-up time gear wheel; a minute hand gear wheel; a fourth intermediate gear wheel; a minute hand alarm ringing gear wheel, having with the same number of toothed gears as the minute hand gear wheel, wherein the fourth intermediate gear wheel and the minute hand alarming gear wheel are sequentially geared with the minute hand gear wheel; a power interrupter provided on each backside of the wake-up time gear wheel, the hour hand alarm connecting gear wheel and the minute hand alarm connecting gear wheel; inner and outer connection rings made of separately conducting materials and provided on each backside of the wake-up time gear wheel, the hour hand alarm connecting gear wheel and the minute hand alarm connecting gear wheel; a parabolic-shaped connection terminal fixedly provided on each front side of the hour hand gear wheel, the hour hand alarm ringing gear wheel and the minute hand alarm ringing gear wheel, the latter being arranged at a position corresponding to the power interrupter; a power source, having the positive terminal thereof connected to a buzzer and the negative terminal thereof, connected to the inner connection ring and a first terminal; and a second terminal connected to the buzzer and the outer connection ring. The alarm system is configured to generate an audio alarm from the buzzer exactly at a desired call time as preset by the user. The wake-up and retiring time setting knobs are designed to remind the user of the wake-up time as well as of the retiring time and a snooze time period of less than one hour.